High voltage switchgear housing with sticky viscous coating for catching metal particles and, thereby protecting the insulators

ABSTRACT

An encased high-voltage switch gear in which the metal parts carrying high voltage current are arranged within a grounded metal sheathing and fixed therein by means of insulating supports, said metal sheathing forming a sealed enclosure and the metal surfaces within said enclosure being at least partly coated with a sticky layer of viscous material, such as polyisobutylene or polyvinylisobutylether, whereby metal shavings present or formed by abrasion within said sheathing will stick to the viscous layer and will not deposit on the insulating supports and reduce their electric insulating properties.

C United States Patent 1 3,553,410

[ Inventor Tibor Mom [56} References Cited (21] A pl N0 glbgiegifelden, Aargau, Switzerland UNITED STATES PATENTS p [22] -Filed Apr. 28,1969 3,356,798 12/1967 McKrnnon 200/148(.2)X [45] Patented Jams 1971 3,432,750 3/1969 Botstiber.... 200/61.09X [73] Assignee Sprecher & Schuh A G FOREIGN PATENTS Aarau, Switzerland 1,244,914 7/1967 Germany 200/ 144(.2) I 32] Pnomy 1968 Primary Examiner-Robert K. Schaefer [33 1 Sw|tzerland 3] N 6641/68 Assistant Examiner-Robert A. Vanderhye I l Attorney-Waters, Roditi, Schwartz &Nissen [54] HIGH VOLTAGE SWITCHGEAR HOUSING WITH STICKY viscous COATING FOR CATCHING ABSTRACT: An encased high-voltage switch gear in which METAL PARTICLES AND, THEREBY th t l t h h t d PROTECTING THE INSULATORS e me a par s carrying lg vo age curren are arrange within a grounded metal sheathm and fixed therein b means 3 Claims 1 Drawing Fig 2 y 00/ 68 of insulating supports, said metal sheathing forming a sealed [52] [1.8. CI 2 l enclosure and the metal surfaces within said enclosure being 174/ 17 200/43, 2 200/148 at least partly coated with a sticky layer of viscous material, [51] Int. Cl. H0lh 33/64, such as polyisobutylen or polyvinylisobutylether, whereby l-IOlh 9/02 metal shavings present or formed by abrasion within said [50] Field of Search ZOO/61.09, sheathing will stick to the viscous layer and will not deposit on 148.2, 144.2, 144.3, 168A(Inquired), 48(Inquired); 174/ l 7(Inquired) the insulating supports and reduce their electric insulating properties.

HIGH VOLTAGE SWITCIIGEAR HOUSING WITH STICKY VISCOUS COATING FOR CATCI-IIN G METAL PARTICLES AND, THEREBY PROTECTING THE INSULATORS This invention relates to encased high-voltage switch gears. Tests have shown that in this type of encased switch gears the flashover voltage may drop considerably owing to deposition of metal shavings on the surface of the insulating supports arranged between the high voltage carrying parts and the grounded metal sheathings. Metal shavings may be produced by assembly work when mounting a switch, or during operation by abrasion at the contacts.

The invention has as its object the provision of means in encased high-voltage switch gears for the prevention of a reduction of the insulating strength, in order to secure an undisturbed operation.

The invention relates to an encased high-voltage switch gear in which the high-voltage carrying metal parts are arranged within a grounded metal sheathing and are secured therein by means of insulating supports, the metal parts within said sheathing being at least partly coated with a layer a viscous material.

The layer of viscous material may for example consist of polyisobutylene or polyvinylisobutylenether. The purpose of the viscous layer is to retain all metal shavings present within the metal sheathing after assembly of the switch or produced during operation at the contacts, at predetermined places, and accordingly keep these shavings away from the surfaces of the insulating supports.

The invention will now be described in detail by reference to the accompanying drawing in which the single FIG. represents diagrammatically a section through a disconnecting switch provided with a ground switch.

The disconnecting switch mechanism shown comprises a contact piece 1 arranged for shifting movement, main and sliding contacts which are built into encasings 2 and 3 and secured to bus bars 4 and 5, and insulating supports 6 and 7 pennitting to fix the bus bars 4 and within the metal sheathings 8 and 9 of the bus bars 4 and 5. A grounded metal sheathing l0 surrounds the switch members and contains a volume of insulating gas sealed within the sheathing with respect to the environment.

The operating member 11 of the disconnecting switch is positively connected to the movable contact 1 by means of a I rotatable insulating rod 12 and any conventional movement transmission means eg rack and pinion 15.

A ground switch consists of a shifting contact member l6 which cooperates with a sliding contact and means for operating the shifting member accommodated in a casing 13. The main contact of the ground switch is mounted within the encasing 2.

The metal shavings forming at the contact places of the disconnecting switchand of the ground switch are retained by a sticky, viscous layer 14 provided at the surfaces of the encasing 2 and of the grounded metal sheathing 10. in this manner, it can be prevented that metal shavings will deposit on the insulating support 6. Instead, any shavings present or formed within the metal sheathing 10 will stick to the viscous layer 14 partly covering the inner wall of the sheathing l0 and the surface of the encasing 2. Thus the electric insulating property of the insulating support will not be reduced.

The soiled sticky layer 14 can be removed by solvents, such as gasoline when the switch undergoes revisions, and afterwards a fresh layer can be applied.

lclaim:

1. An encased high-voltage switch gear having high voltage carrying metal switching members, a grounded metal sheathing surrounding said switching members and forming a sealed enclosure filled with insulating gas, insulating supports for securing said switching members within said sheathing, a portion at least of the metal surfaces within said metal sheathing bein coated with a layer of sticky, viscous material. 2. A high-v0 tage voltage switch gear according to claim I, 

1. An encased high-voltage switch gear having high voltage carrying metal switching members, a grounded metal sheathing surrounding said switching members and forming a sealed enclosure filled with insulating gas, insulating supports for securing said switching members within said sheathing, a portion at least of the metal surfaces within said metal sheathing being coated with a layer of sticky, viscous material.
 2. A high-voltage voltage switch gear according to claim 1, in which said layer of viscous material consists of polyisobutylene.
 3. A high-voltage switch gear according to claim 1, in which said layer of viscous material consists of polyvinylisobutylether. 